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    <title>Document</title>
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    <script>
        var grade = parseInt(prompt('请输入分数'))
        var t = Math.floor(grade / 10)
        if (t == 10 || t == 9) {
            alert("你的成绩等级为优秀");
        } else if (t == 8 || t == 7 || t == 6) {
            alert("你的成绩等级为良好");
        } else {
            alert("你的成绩等级为不及格，继续加油哦！");
        }
    </script>
</body>
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